Footwear with soles containing rubber



March 28, 1961 E. E. ROLLMAN y 2,976,624

FOOTWEAR WITH SOLES CONTAINING RUBBER Original Filed June 24, 1952INVENTOR ERNEST E. ROLLMAN BY QM l fla/ila!! ATTORNEY 1nited States2,976,624 FOOTWEAR WITH SOLES CONTAINING RUBBER Ernest E. Rollman,Waynesville, N.C., assignor to Roearclh, Inc., Waynesville, N.C., acorporation of North aro ma Original application June 24, 1952, Ser. No.295,247, now Patent No. 2,789,295, dated Apr. 23, 1957. Di-v vided andthis application Nov. 6, 1956, Ser. No. 620,699

3 Claims. (Cl. 36-14) atent f which the lower margin of the upper ispulled over the li edge of a last and tacked to an insole previouslyplaced on the last. This insole is the element which holds the shoebottom in the desired spatial position. The lasting is a relativelyexpensive operation and sometimes omitted for this reason, and replacedby providing a sock lining stitched to the lower margin of -the upper. Alast is slipped thereafter in the so-prepared sock, although theso-obtained t of the upper on the last is at best incomplete. v

According to the invention the expensive preliminary operation oflasting can be omitted, and the t of the footwear improved by tighteningthe upper on the last, and securing the lower margin of the upper orparts connected thereto to a rubber layer set and vulcanized While theupper is held tightened. This eliminates not only the need for an insoleas a structural part, which often has to be expensively pre-shaped, butassures a firm and resilient shoe bottom. it is advisable to use aheated last so as to obtain simultaneously a better and more permanentstretching and fitting of the upper and a proper and fast curing o-f therubber.

The invention and its advantages are further clarified in the drawingswhich sho-w in Fig. l a cross-section of the edge of a shoe. Fig. 2shows in a similar cross-section the edge of the shoe of a modifi-edform. Fig. 3 shows in a similar cross-section an execution where arubber layer forms the main sole. Fig. 4 shows in a similar View theedge of a shoe in which the rubber sole is enclosed by the platformwrapper. Fig. 5 shows in a similar cross-section the edge of a shoe withthe sole formed by the upper, Welt and the rubber layer.

As shown in Fig. l, the upper 1, which might be partly or completelylined prepared in the usual way by stitching together various pieces ofleather or fabric, is provided on its lower rim with an outwardprotruding extension formed by a welt 3, which might be a strip ofleather stitched at 4 to the upper 1. An outsole 5 in turn is stitchedat 6 to the Welt 3, the latter being of such thickness so as to leavespace for a midsole oetween the last 8 and the outsole 5. Material forthe midsole which comprises a layer 7 of felt, or similar material and alayer 9 of rubber mix, preferably to form porous rubber, is placed uponthe last 8 and said upper is slipped over it, together with the welt andoutsole This can be done easily, as the upper is still of baggyappearance and does not yet fit the last tightly. A lip 10 which may bedivid-ed into various segments and is part of the mold enclosing theshoe bottom, is then placed against the lower rim of the upper into thegroove formed 2,976,624 Patented Mar. 28, 1961- by the lower rim of theupper and the welt 3. The segments are moved then towards the center ofthe sole and thereby the upper is tightened on the last-by pushing itslower rim inwards. This is the state shown in Figs. l and 2. Theassembly is then subjected to heat, preferably by heating the last 8.Under the influence of the heat, the rubber mix will expand and ll thespace between the last and the outsole, and simultaneously bond to themargin of the upper welt as well as to the outsole. As the porous rubberis completely enclosed by the `leather welt and outsole, the shoe willoffer better appearance and better resistance to wear than shoes withexposed porous rubber surfaces.

AAs shown in Fig. 2 the upper 1 might be stitched to the welt 3 by theseam 4 in such way that the rubber mix contacts only a part of theextension of the upper, not directly the welt strip- 3. Withoutdeviation from the invention it might be of advantage to tighten theupper not by moving the lower rim inwards, but by holding the lower rimof the upper in the desired spatial relation while the upper istightened by expandingv the last. Various types of foreshortening lastsmight be used, but I found that metal lasts with inserted electricheating elements are preferable. The lower rim of the upper can be heldin the desired spatial relation by segmented lips 10 or by the outsoleand welt, if the shoe bottom offers the rigidity to hold the lower rimof the upper in its place vwhile the upper is stretched and the rubberlayer vulcanized. Y

rI'he term lower margin of the upper is used here to designate the veryend of the upper usually used for the lasting operation, while the termlower rim of the upperis used to designate that part of the upperadjacent to, or forming part of, the outwardly extending vrimA of thesole. The lower rim of the upper might be formed by the material of theupper or by a strip fastened to the upper. The term shoe bottom is usedhere to designate those parts of the shoe which hold the lower margin ofthe upper and is formed in the examples shown inthe drawingssubstantially by the rubber layer 9.

The term outward extension is used here to designate that part of a shoewhich extends essentially horizontally outwardly from the lower rim ofthe upper to cover at least the upper rim of the sole. The outwardextension might be a strip of material such as leather stitched to theupper, or it might be an outwardly turned part of the upper itself,which ends at the edge of the sole or continues downwardly to cover theside of the sole.

The method according to the invention is also used to advantage forshoes with platforms, as shown in Fig. 3, where the parts correspondingto those of Figs. l and 2 are designated by the same numerals; Here aplatform wrapper 11, is shown stitched at 4 to the upper 1 to form againan outward extension and thereby a crease between the lower rim of theupper and the upper rim of the sole. During the heating of the shoe onthe last 8 the rubber mix 9 expands and fills the platform completely.Once set, the expanded rubber will assure the maintenance of the desiredshape of the platform and the shoe. If the wrapper 11 is not stiff'enough to assure the -desired contour of the platform during the curingof the rubber, an auxiliary mold comprising a frame 12 and a sole plate13 might be used to limit the space of the expansion of the rubber. Asshown in Fig. 4, the platform wrapper might be a piece of the upper 1,cut correspondingly larger and fastened to an outsole 5 before placingit on the last 8. The crease between the upper and the platform isproduced by pushing into place the lip 10.

Fig. 5 shows a cross-section of the edge of a shoe in which the upper 1,to which a welt 3 has been fastened by the stitching 4, is held in thedesired shane by the rub- 3 ber sole 9 molded and vulcanized in situ. soas to hold the lower margin of the upper resiliently in the desiredpermanent position and to enclose at the same time a lller 7. Itdesired' a tread sole might be added after molding and vulcanization,but the shoe will be comfortable and durable also without such tread orwear Sole.

For other types of footwear the methods described above might be alteredwithout deviation from the ini vention. The composite sho-e bottom shownIin Fig. 2 might be replaced by a layer of rubber just strong enough tohold the margin of the upper in the desired spatial position and mightthen be less porous and more rigid as shown in Fig. 3, where the lowerrim of the upper 1 is extended by the ywelt 3, which is placed behindthe lip 10. The rubber layer 9, forming the sole, is contained betweenthe frame 12 and the bottom plate 13 of the mold. Here again the rubberis sealed against the mold lip by the welt Seven if only very little orno pressure is exerted between the lip 10 and the upper 1. If rubber ofsufficient strength is used it is possible for some types of footwear touse only a welt-like strip of rubber vulcanized to the lower margin ofthe upper to assure that the shoe bottom maintains its position, alsoafter flexing it. In this instance as well as in other cases it might beof advantage to sew the outsole to the welt only after the vulcanizationof the rubber or to prevent by other means the adherence of the rubberlayer to the outsole, as then a worn outsole can be replaced easilywithout damage to the firm land waterproof shoe bottom.

The term rubber is used here for any natural synthetic elastomer withqualities similar to those of rubber obtained from the Hevea plant.According to the type of elastomer used, the setting might occur atnormal or elevated temperature.

This application is a division of parent application Serial No. 295,247,led June 24. 1952, now Patent No. 2,789,295.

What I claim and desire to secure by Letters Patent is:

1. A shoe comprising material forming a shaped upper, said upper havinga lower inturned marginal portion and an outwardly extending welt joinedto said lower marginal portion, and a sole layer 01:" rubber molded andvulcanized in situ directly to the inner portion of said welt and tosaid lower marginal portion of said upper, said sole constituting theonly structural element secured to said upper and Welt at the region oftheir joinder and holding in position opposite sides of said lowermarginal portion of said upper to maintain said upper in its givenshape.

2. A shoe as claimed in claim l further characterized in that said Weltis formed integrally with said upper. i

3. A shoe as claimed in claim 1 further characterized in that said weltis a `separate strip of material stitched to the lower marginal portionof said upper, one face of the stitching being embedded in said solelayer.

References Cited in the le of this patent kUNITED STATES PATENTS 772,027Buttereld Oct. 11, 1904 774,865 Butterfield Nov. 15, 1904 1,138,961Langenohl May 11, 1915 1,374,480 Trull Apr. 12, 1921 1,706,126 Peer etal Mar. 19, 1929 2,046,444 Belyea. July 7, 1936 2,129,106 .SzerenyiSept. 6, 1938 2,283,953 Rohrer May 26, 1942 2,574,582 Rollm-an Nov. 13,1951 2,651,118 Root Sept. 8, 1953 FOREIGN PATENTS 1,631 Great BritainJan. 20, 1913 310,495 Germany Jan. 25, 1919 244,800 Great Britain Ian.6, 1927 366,881 Italy Jan. l1, 1939 667,837 Great Britain Mar. 5, 1952

